1. Field of the Invention
The present invention relates to a protective film for polarizers. In particular, the invention relates to a protective film for polarizers, in which the amount of the additive is reduced.
2. Description of the Related Art
Heretofore, films comprising a cellulose resin (e.g., cellulose acylate resin) as the main ingredient are used as protective films for polarizers (See Patent References JP-A 2006-89529, JP-A 2006-111842 and JP-A 2007-108641). For making them have a retardation, the films are stretched or a retardation enhancer is added thereto. However, the stretching is problematic in point of the cost, as requiring an additional working step. Addition of a retardation enhancer is also problematic in that the saponification liquid for use in the saponification step in film production is often contaminated.